Colin Turkington will race in three rounds of the World Touring Car Championship this season with the WSR BMW squad
Turkington, 28, has not raced since winning the British Touring Car title with WSR last year, but will make his return to Dick Bennetts' squad at the Algarve circuit on July 4.
"I feel this is a natural progression for me after last year's championship," said Turkington.
"Obviously I know the WSR guys very well. They're a top team and have been a big part of my success in recent years. I'm also indebted to Dick because he's been working so hard over the past few months to make this a reality."
Following the Algarve round, Turkington will also take part in the Brands Hatch and Brno events.
WSR's initial three-round deal could be expanded to include further races before the end of the season, and Turkington hopes to take in a full campaign in 2011.
Turkington took part in two WTCC rounds in 2007, finishing on the podium at Brands Hatch and later racing at Macau, each time also with WSR.
WSR's BTCC programme with Rob Collard and Andy Neate will not be affected by Turkington's signing.
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